Why do serial delays not accumulate in time spent per message?
given a pattern such as: 
where each delay is 2s, why is 2s between each message logged, and not 8s?
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since there is nothing to block the emission of the message from the final delay, the serial delays function as a queue. when a message is shuffled to the next delay in sequence, the message is held there for 2s. this is true for 4 messages. when we add a gate:
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